ES2298921T3 - OSEA PLATE. - Google Patents

Abstract

The bone plate has a lower surface (3) and a top side (2) as well as holes arranged on a disk longitudinal axis which provide for anchorage of bone screws (9, 11). One of the holes is designed as a constant slotted hole (4) where in a subrange of the side edge of the longitudinal hole thread courses (5) are provided. The thread courses (5) are arranged in a direction transverse to the level of the top side (2) and an even retaining structure (6) is provided for a positive interference with a structure (14) at a screw head (10, 12) and or neck of a bone screw (9, 11).

Description

Bone plate

The invention relates to a plate of bone.

Bone plates are known from CH 462375, WO 2000/53111, WO 2001/54601 or EP 0760632 B1.

The configuration of the holes in this state of the technique is such that they consist of the combination of two holes that overlap with different diameters and that are combined with a passage hole and each side of the passage hole with its fixed diameter it presents its own functionality and must be also contemplated separated from each other.

Thus, for example, it is not possible to insert over the proportional side of the thread of the passage hole a screw standard cortex, but only a screw with a thread of head.

The other side of the passage hole, which does not It has some threaded part, it is suitable only for Introduction of a standard cortical screw, which can be also applied with compression and angle variability.

Therefore, the holes also completely from each other, since no they present any functional cut-off point.

This disadvantage is then also extended by the entire application, because when introducing a cortical screw standard attention should also be paid to meet also always on the right side of the hole.

A screw is known from US 2004/0087951 A1 of bone that presents in its screw head, seen in the direction of the longitudinal axis of the screw, arranged one above the another, a threaded section and smooth wall sections. These smooth wall sections serve for the articulated housing of the screw in corresponding guides.

Starting from this, it is the task of the invention improve the chances of using a bone plate and increase Your flexibility in handling.

This task is solved by a plate of bone with the characteristics of claim 1. The Advantageous improvements are indicated in the dependent claims 2 to 8. In claim 9 is finally indicated a bone plate system according to the invention and at least one bone screw that fits with that, which It can be considered together as a fixing system.

It is essential in the invention for the new plate of bone that, seen in a direction transverse to the plane of its upper side, both a thread and a structure of smooth wall clamp are arranged arranged one above the another in the same way in a partial section. Through action Joint thread and smooth wall clamping structure, can be maintained a bone screw configured with contratructures corresponding, fixed in position especially Effective in bone plate. Through the joint action of the thread in the oblong hole with a shaped counter nut correspondingly on the head or neck of the screw bone, the bone screw is pressed with a counter structure or support structure shaped so that it corresponds to the clamping structure firmly in this clamping structure and it is thus securely fixed.

In this case, it's basically the same if, seen from the top side of the plate, the clamping structure is arranged first and the thread is arranged in the area lower bone plate or vice versa. They can also be provided several threaded sections on the bone plate alternately and each time interrupted by at least one section with a clamping structure. An example of embodiment, in which the threaded section is near the top side of the bone plate and a clamping structure will found near the bottom side of the bone plate (compare claim 4).

According to the invention, the hole section oblong provided with thread and clamping structure is limited to a partial section of the oblong hole, that is located preferably on a narrow side of the oblong hole (compare claim 8).

In particular, it is planned in a advantageous improvement that the thread surrounds, seen in the plane of the surface, at most 180º of a circular perimeter of a head or neck of a bone screw that must be engaged in that. This configuration causes a bone screw to be freely movable along the longitudinal axis of the hole oblong, and can therefore be used to apply a force of directed pressure on the fractured point to fix the fixed angle plate.

Currently, a surface is preferred partially spherical as a clamping structure. In this one, you can a surface correspondingly formed to be fixed spherical or partially spherical of the head or neck of the screw of bone Mainly, it is also possible to use other forms of the surfaces of clamping structures, for example conical

A puncture planned according to an improvement advantageous according to claim 5 in the transition zone between the thread and the clamping structure facilitates a Screw head or neck transfer, more exactly from the same area provided with a thread, to the section of the oblong hole provided with the thread, especially in a bone screw displacement along the hole oblong.

In a configuration according to claim 6, it is provided that the oblong hole has a structure of peripheral guide on the upper side of the bone plate. This It serves to guide the head or neck of a bone screw. This guide structure can be for example a peripheral edge with cross section configured with a primitive circle shape, in which a formed counter-structure can slide correspondingly spherical or partially spherical next to the head or neck of a bone screw. According to claim 6, the guide structure defines a guide plane. This guide plane is that plane, inside which slide a point in the head of the screw if the screw is displaced along the guide structure. In addition, this plane guide is cut by a longitudinal axis of the thread, this is in the sense of the invention the axis around which a counter to screw on the thread in a threading process, by An angle to move of 90º. This type of tilt between the thread and the guide plane also causes a maximum link 180º located in the plane of the surface the thread or the structure clamp give the head or threaded neck a support sure, since the slope results in a link effectively continued at least in a partial area of the thread. This effect is achieved by a "tightening effect" or "keying effect" caused due to tilting.

In addition, it is preferred that the guide plane be inclined with respect to the plane surface (claim 7) by an angle between 0º and 90º. Here, a variant embodiment, in which the thread or structure of clamping are arranged in a section of the oblong hole in the which the guide plane is located at greater depth, that is, farther from the upper side of the bone plate (compare the claim 8).

By oblong hole in the direction of this invention is understood not simply an image of the hole caused by the displacement of a circle along an axis straight, but essentially any form of opening that in a first extension address is longer than in a second direction of extension and that runs continuously, that is, without "barriers" that penetrate the hole. Therefore a oblong hole may be shaped in the direction of the invention also "narrowing triangularly" and being oval.

With the invention, finally still a system consisting of a bone plate and a bone screw as described above. The bone screw of this system has according to the invention a screw head or neck of screw, next to which, arranged one above the other and arranged in a manner adapted to the corresponding counter-structures in the bone plate, has a threaded structure and a structure of support configured in a complementary way to the structure of oblong hole clamping.

The bone plate can be fixed and tensioned stable way at an angle simultaneously with a bone screw, configured in a special way. However, here it should be emphasized that the bone plate according to the invention can also be fixed with standard bone screws or bone screws supported by such standard bone screws, which do not present in particular neither a thread nor a support structure on its head, that is, neck screw

Overall, it is preferred that in a oblong hole configuration with guide structure be formed a section of a bone screw corresponding to system, shaped according to the invention (for example the thread) in its outer contour according to the cross section of the structure guide, so that also a bone screw according to the invention can be guided in the guide structure. By consequently, a bone screw can also be applied otherwise shaped to fix the bone plate so stable at an angle to the "tension" of the bone plate.

The bone plate according to the invention offers (also together with the bone screw corresponding to the system) a large number of possibilities of use, which makes it suitable for Fix the most diverse fractures.

For this, particularly preferred is that all openings in the bone plate are shaped as oblong holes with the features according to the invention.

Other advantages and features of the invention result from the following description of an exemplary embodiment by means of the attached figures. Here they show:

Fig. 1 an exemplary embodiment for a plate of bone according to the invention in a three-dimensional view,

Fig. 2 the bone plate of Figure 1 in a view from above,

Fig. 3 in an enlarged section, the side bottom of the bone plate of Fig. 1,

Fig. 4 in an enlarged representation, the side bottom of an alternative configuration of a bone plate according to the invention,

Fig. 5 a cross section through a bone plate of Fig. 1 along its longitudinal plane central,

Fig. 6 in enlarged representation, a section cross section corresponding to Fig. 5 with only an oblong hole  represented,

Fig. 7 a representation as in figure 6 with development of the guide structure included for the illustration,

Fig. 8 a view of a bone screw standard,

Fig. 9 a view of a bone screw according to the invention comparable to Fig. 8 for joint action with the thread and the clamping structure in the bone plate according to the invention,

Fig. 10 in a schematic representation, a standard bone screw inserted into an oblong hole of the bone plate according to the invention,

Fig. 11 a representation similar to Fig. 10 with the standard bone screw in another position,

Fig. 12 a representation comparable to the Fig. 10 with a bone screw according to Fig. 9 instead of the screw of standard bone,

Fig. 13 a bone screw according to Fig. 9 fixed on the thread and on the clamping structure,

Fig. 14 a view of the bone plate according to the invention with drill sleeve placed on a bone for drilling a screw hole, and

Fig. 15 a view similar to Fig. 14 but with an alternative variant of a chuck.

The figures schematically show a exemplary embodiment of a bone plate according to the invention and generally indicated with 1. The embodiment example shown does not fit the scale in any case, but serves Simply for a main clarification.

The bone plate 1 according to the invention has an upper side and a lower side 3 that serves to support the bone to be fixed. Continuous openings in the form of oblong holes 4 are inserted between the upper side and the lower side. The oblong holes 4 are continuous, that is, without possible projections running inwards or similar obstacles. The bone plate 1 according to the invention has in this embodiment a total of eight oblong holes 4, but not limited to this number. The oblong holes 4 in the preferred embodiment are formed by narrowing towards one of the longitudinal sides. They can, however, as shown for example in an alternative configuration according to Fig. 4, also run in a straight way and correspond to the shape as it occurs by moving a circle along a predetermined path. Naturally, all other forms of thinkable oblong holes are also possible, as long as they are configured continuously, that is, without obstacles in their
inside.

On one front side of each oblong hole are formed a thread 5 as well as a clamping structure 6. The thread 5 and the clamping structure 6 are in a transverse direction to the plane of the plate arranged one above the another, the thread 5 being arranged in this embodiment above (directed towards the upper side 2 of the bone plate 1) and the clamping structure 6 below (directed towards the lower side 3 of the bone plate 1). In the transition zone between thread 5 and the clamping structure 6 is introduced a puncture 7. The clamping structure 6 is formed by a wall section smooth, partially spherical oblong hole.

As seen especially in figures 1, 2 and 3, in the exemplary embodiment shown the threads 5 and the clamping structures 6 of the oblong holes 4 are arranged on narrow sides of the latter, and indeed on the narrow narrow sides that are oriented each in center direction of the plate. In this case, the axes Longest longitudinal oblong holes 4 extend to along a longitudinal axis of the plate.

The oblong hole 4 contains a structure of peripheral guide 8 in its opening facing the upper side 2 of the bone plate 1. This is formed by an edge with cross section in the form of a primitive circle, which is introduced into oblong hole 4 for example by a step of processing by chip removal (e.g. milling). In the Figure 7 has been drawn for that purpose for illustration a development of this "bathtub-like" edge, that is, of the guide structure 8. Here it is also particularly well observed that the guide structure 8 is inclined by an angle? with respect to the development of the plate plane E_ {p} established  by developing the upper side 2 of the bone plate 1. In the same way the guide plane is also inclined E_ {L} with respect to a longitudinal axis of thread A_ {G}, and of made by an angle β.

Figures 8 and 9 show a screw of standard bone 9 (Fig. 8) with a screw head 10 formed smooth and spherical on the lower side or a bone screw 11 (Fig. 9) designed with a screw head 12 especially for the joint action with bone plate 1 according to the invention. The Screw head 12 contains a thread 13 on top, spherically configured in this embodiment and, seen in  direction of the longitudinal axis of the screw, below a section with a support structure 14. This support structure 14 is made with smooth wall with spherical or partially developed spherical, and is complementary to the shape of the structure of clamping 6 of the bone plate 1.

Figures 10 to 13 show the action joint between a bone screw 9 of the conventional type or a bone screw 11 of the type adapted according to the invention and of the bone plate 1 according to the invention. Thus, it must now be explained by middle of these figures also the operation of the plate bone according to the invention 1 and its elements.

In figures 10 and 11 it is represented in two different positions a conventional bone screw 9, inserted into oblong hole 4 of bone plate 1. This bone screw rests with the bottom side formed smooth spherical of the screw head 10 on the guide structure 8 formed in addition to the oblong hole 4 and can be then moved along the guide plane E_ {L} along of the longitudinal axis of the oblong hole 4. Through the position inclined from the guide plane E_ {L}, an effect of compression by screwing the bone screw 9, pressing the bone plate 1 in one direction, that is, pulling a bone to fix with it in the other direction. As seen in the figure 11, the teeth of the thread 5 pointing towards the inside of the oblong hole 4 are formed in such a way that they form also a guide surface made in addition to the lower side of the screw head 10 conically formed. By consequently, this is a constituent part of the component of the guide structure 8. On this guide surface the conventional bone screw 9 with respect to the perpendicular (according to the direction of the threaded shaft A_ {G}). This provides a large number of possibilities to fix the bone screw 9 in bone. This slope is not only possible here in one direction at length of the longitudinal axis of the oblong hole, but also in transverse directions to that one, so that it eventually turns out an area of essentially 360º, in which the screw with respect to the threaded shaft A_ {G}.

Said conventional bone screw 9 may be used with bone plate 1 according to the invention to achieve a compression effect However, this screw is not suitable bone to achieve stable angle fixation on the plate bone 1 and bone. For this, the bone screw can be used 11 adapted according to the invention to the bone plate, as described below by means of figures 12 and 13.

The screw head section 12 provided of the thread 13 has an outer contour (an envelope of the thread steps), which is equally spherical and complementary to outline of the guide structure 8. In this way, the screw bone 11 can also be guided in the guide structure 8, such as bone screw 9. Thus, bone screw 11 can also be used first to achieve an effect of compression. However, the particularity of bone screw 11 is that it can be fixed in a stable position in the hole oblong 4 of the bone plate 1. This situation is represented in figure 13. In this position, the thread 13 of the head of the screw 12 engages the thread 5 in the oblong hole 4, and the support structure 14 relies on positive union in the structure clamping 6. Through the joint action of thread 5 and 13, press the support structure 14 firmly against the structure of clamping 6, in which it should be noted that the structure of clamp 6 and thread 5 are also configured in a similar way coaxial, such as thread 13 and head support structure 14 of screw 12. The transition of screw head 12, more exactly from the thread 13 in the screw head 12, to the thread 5 in oblong hole 4 is facilitated by puncture 7. Here, The thread pitch principle of thread 13 can be transferred securely inside the thread 5, so that finally that gear in thread 5 without tilting.

In a position as shown in Figure 1, the thread 5 envelops the head of the screw 12, that is, the thread 13 therein, seen on a plane of the surface 2 of the plate bone 1, seen around a maximum 180º. Screw 11 is held in position, due to a tightening effect achieved by tilting the guide plane E_ {L} with respect to the axis longitudinal thread A_ {G}.

Only because of the last fact mentioned is possible to configure the oblong hole 4 usable effectively continuously and for the entire length alternatively for compression or for stable fixation in angle.

In figures 14 and 15 it is represented how chucks are attached with the bone plate for the operation for the incorporation of the bone plate. The situation shown in figure 14 shows a drill sleeve 15 simple, which is screwed with the spherical thread 16 formed in its lower end and support structure (corresponding to the screw head structures 12 of bone screw 11) in the thread 5 and the clamping structure 6 on the inner side of the oblong hole 4. The drill sleeve 15 predetermined in inside a perforated channel 17 that extends through the Thread housing 16 exactly adapted and structure of support of the chuck 15 along the axis A_ {G}. The chuck 15 serves as an auxiliary element for ensure at the beginning of the bone perforation to be provided with the bone plate 1 that the perforated hole extends perpendicularly with respect to bone plate 1 and thus can screw a bone screw 11 into the bone so stable at an angle, so that its screw head 12 with the thread 13 and support structure 14 engage smoothly in the thread 5 or in the clamping structure 15.

A variant is shown in Figure 15, in that another drill sleeve 18 is placed on a bushing chuck 15 so that the perforated channel 19 of this drill sleeve 18 is exactly so parallel to the A_ {G} axis. With this chuck 18 they can drill screw holes in the bone, which allow the double function described above of a bone screw 11. The bone screw 11 is screwed in this case at an angle perpendicular to the bone that allows it to slide first for a compression along the oblique plane E_ {L} of the guide structure 8 and then engage with thread 13 and the support structure 14 on its screw head 12 securely and not tilted on the thread 5 or the clamping structure 6 on the inner side of oblong hole 4, to finally be fixed in your angle This process finally allows simultaneous compression. and angle fixing with only one screw in one phase of the job.

The chucks shown are purely exemplary and there are different ways to achieve the same results with drill bushings constructed in a manner different.

List of reference symbols

one

Bone plate

2

Top side

3

Lower side

4

Oblong hole

5

Thread

6

Clamping structure

7

Puncture

8

Guide structure

9

Bone screw

10

Screw head

eleven

Bone screw

12

Screw head

13

Thread

14

Support structure

fifteen

Drill Chuck

16

Thread

17

Perforated channel

18

Drill Chuck

19

Perforated channel

A_ {G}

Longitudinal Thread Shaft

HE}

Guide plane

E_ {P}

Plate plane

α

Angle

\beta

Angle

       \ vskip1.000000 \ baselineskip
    

Documents cited in the description This list of related documents by the applicant has been collected exclusively for reader information and It is not part of the European patent document. That has been made with the greatest diligence; however, the EPO does not assume any responsibility for possible errors or omissions Patent documents cited in the description

CH 462375 [0002]

WO 200053111 A [0002]

WO 200154601 A [0002]

EP 0760632 B1 [0002]

US 20040087951 A1 [0008]

Claims (9)

1. Bone plate (1) with a lower side (3) configured for support in the bone and an upper side opposite the bone (2), as well as with a multitude of holes provided essentially along the longitudinal axis of the bone. plate, through which for anchoring bone screws (9, 11) can be meshed with the bone, in which at least one of the holes is made as a continuous oblong hole (4), with the longest axis in direction of the longitudinal axis of the plate, thread passages (5) being provided in a partial area of the side edge of the oblong hole, which are arranged, seen in a direction transverse to the plane of the upper side (2), only on one side of the depth of the oblong hole (4), characterized by the fact that above and / or below the thread passages (5), seen in the direction transverse to the plane of the upper side (2), is a structure for clamping (6) with a smooth wall to engage in joint po Sitiva with a counter-structure (14) correspondingly configured in a screw head or neck (10, 12) of a bone screw (9, 11). 2. Bone plate according to claim 1, characterized in that the thread passages (5) surround, seen in the plane of the surface (3), at most 180 ° of a circular perimeter of a screw head or neck (10, 12) of a bone screw (9, 11) to be engaged with it. 3. Bone plate according to one of the preceding claims, characterized in that the clamping structure (6) is a partially spherical surface. 4. Bone plate according to one of the preceding claims, characterized in that the thread passages (5) are arranged in a section located near the upper side (2) of the bone plate (1), the structure of clamping (6) in a section arranged near the bottom side (3). 5. Bone plate according to one of the preceding claims, characterized in that a puncture (7) is provided in a transition zone between thread passages (5) and the clamping structure (6). A bone plate according to one of the preceding claims, characterized in that the oblong hole (4) has on the upper side (2) of the bone plate (1) a peripheral guide structure (8) for the head guide (10, 12) or the neck of a bone screw (9, 11), in which the guide structure (8) defines a guide plane (E_ {L}) and this guide plane ( E_ {L}) is cut by a longitudinal axis of the thread formed by the thread passages (5) around an angle (?) Different from 90 °. 7. Bone plate according to claim 6, characterized in that the guide plane (E_ {L}) is inclined with respect to the plane of the plate (E_ {P}) around a higher angle (α) at 0º and less than 90º. A bone plate according to claim 7, characterized in that the thread passages (5) are arranged on a narrow side of the oblong hole (4), preferably symmetrically with respect to its longer axis, as far as which the guide structure (8) has the greatest distance to the upper side (2) of the bone plate (1) in this area of the oblong hole (4). 9. System composed of a bone plate (1) according to one of the preceding claims and at least one screw bone (11), where the bone screw (11) presents in a head and / or screw neck (12) in one direction along its longitudinal axis, arranged one after the other, in a first zone, a thread (13), and in a second zone, a structure of support (14) made in addition to the support structure (6) of the oblong hole (4) of the bone plate (1).